9999900099971 has 2 divisors, whose sum is σ = 9999900099972. Its totient is φ = 9999900099970.

The previous prime is 9999900099967. The next prime is 9999900100007. The reversal of 9999900099971 is 1799900099999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9999900099971 - 2² = 9999900099967 is a prime.

It is not a weakly prime, because it can be changed into another prime (9999900099571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4999950049985 + 4999950049986.

It is an arithmetic number, because the mean of its divisors is an integer number (4999950049986).

Almost surely, 2^{9999900099971} is an apocalyptic number.

9999900099971 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999900099971 is an equidigital number, since it uses as much as digits as its factorization.

9999900099971 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 301327047, while the sum is 80.

The spelling of 9999900099971 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred million, ninety-nine thousand, nine hundred seventy-one".